SPDX: Convert all of our single license tags to Linux Kernel style

When U-Boot started using SPDX tags we were among the early adopters and
there weren't a lot of other examples to borrow from.  So we picked the
area of the file that usually had a full license text and replaced it
with an appropriate SPDX-License-Identifier: entry.  Since then, the
Linux Kernel has adopted SPDX tags and they place it as the very first
line in a file (except where shebangs are used, then it's second line)
and with slightly different comment styles than us.

In part due to community overlap, in part due to better tag visibility
and in part for other minor reasons, switch over to that style.

This commit changes all instances where we have a single declared
license in the tag as both the before and after are identical in tag
contents.  There's also a few places where I found we did not have a tag
and have introduced one.

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/arch/arm/mach-mvebu/serdes/axp/Makefile b/arch/arm/mach-mvebu/serdes/axp/Makefile
index a380fee..897afb7 100644
--- a/arch/arm/mach-mvebu/serdes/axp/Makefile
+++ b/arch/arm/mach-mvebu/serdes/axp/Makefile
@@ -1,6 +1,4 @@
-#
-# SPDX-License-Identifier:	GPL-2.0+
-#
+# SPDX-License-Identifier: GPL-2.0+
 
 obj-$(CONFIG_SPL_BUILD)	= high_speed_env_lib.o
 obj-$(CONFIG_SPL_BUILD)	+= high_speed_env_spec.o
diff --git a/arch/arm/mach-mvebu/serdes/axp/board_env_spec.h b/arch/arm/mach-mvebu/serdes/axp/board_env_spec.h
index c8d9485..9c3e7c0 100644
--- a/arch/arm/mach-mvebu/serdes/axp/board_env_spec.h
+++ b/arch/arm/mach-mvebu/serdes/axp/board_env_spec.h
@@ -1,7 +1,6 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 /*
  * Copyright (C) Marvell International Ltd. and its affiliates
- *
- * SPDX-License-Identifier:	GPL-2.0
  */
 
 #ifndef __BOARD_ENV_SPEC
diff --git a/arch/arm/mach-mvebu/serdes/axp/high_speed_env_lib.c b/arch/arm/mach-mvebu/serdes/axp/high_speed_env_lib.c
index 525576a..569840f 100644
--- a/arch/arm/mach-mvebu/serdes/axp/high_speed_env_lib.c
+++ b/arch/arm/mach-mvebu/serdes/axp/high_speed_env_lib.c
@@ -1,7 +1,6 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Copyright (C) Marvell International Ltd. and its affiliates
- *
- * SPDX-License-Identifier:	GPL-2.0
  */
 
 #include <common.h>
diff --git a/arch/arm/mach-mvebu/serdes/axp/high_speed_env_spec.c b/arch/arm/mach-mvebu/serdes/axp/high_speed_env_spec.c
index 704a59f..539d237 100644
--- a/arch/arm/mach-mvebu/serdes/axp/high_speed_env_spec.c
+++ b/arch/arm/mach-mvebu/serdes/axp/high_speed_env_spec.c
@@ -1,7 +1,6 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Copyright (C) Marvell International Ltd. and its affiliates
- *
- * SPDX-License-Identifier:	GPL-2.0
  */
 
 #include <common.h>
diff --git a/arch/arm/mach-mvebu/serdes/axp/high_speed_env_spec.h b/arch/arm/mach-mvebu/serdes/axp/high_speed_env_spec.h
index e10574e..b920f5e 100644
--- a/arch/arm/mach-mvebu/serdes/axp/high_speed_env_spec.h
+++ b/arch/arm/mach-mvebu/serdes/axp/high_speed_env_spec.h
@@ -1,7 +1,6 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 /*
  * Copyright (C) Marvell International Ltd. and its affiliates
- *
- * SPDX-License-Identifier:	GPL-2.0
  */
 
 #ifndef __HIGHSPEED_ENV_SPEC_H